1. Field of the Invention
The present invention relates to electrical contacts, more particularly, to methods of manufacturing crimp ears.
2. Description of the Related Art
The typical electrical contact has a contact portion and a crimp ear for attaching a wire. The inner surface of the open barrel or closed barrel crimp ear is serrated to provide a more secure wire attachment, where the serration may take the form of grooves or ridges. The simplest form is a groove that extends laterally across the face of the crimp ear to indent and clinch the outer layers of multi-stranded or single bare wire. Other forms are known in the art for providing a better bare wire connection or that pierce insulation.
A number of different serration cross-sectional profiles are known in the art. U.S. Pat. No. 3,549,786, issued to Kuo, discloses a serration that rises from a base below the crimp ear surface to a sharp edge above the crimp ear surface. The profile has a flat face perpendicular to the crimp ear surface and a face that curves downwardly and outwardly from the sharp edge. U.S. Pat. No. 3,735,331, issued to O'Donnell et al., discloses a groove below the surface of the crimp ear. The profile has a face that slopes into the groove and slightly away from the center of the groove and another face the slopes into the groove and substantially toward the center of the groove. U.S. Pat. No. 3,812,448, issued to Haitmanek, discloses a serration with several different profiles. The common thread is that one face extends upwardly from the crimp ear surface while the other face extends upwardly from below the crimp ear surface. The two faces meet at a point.